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Old 26-07-2014, 11:55 PM   #41
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Lightbulb Mu Cluster

Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from the Greek Βοώτης, Boōtēs, meaning herdsman or plowman (literally, ox-driver; from boos, related to the Latin bovis, “cow”).. The "ö" in the name is a diaeresis, not an umlaut, meaning that each 'o' is to be pronounced separately..Boötes was one of the 48 constellations described by the 2nd century astronomer Ptolemy and is now one of the 88 modern constellations.. It contains the fourth brightest star in the night sky, Arcturus..In ancient Babylon the stars of Boötes were known as SHU.PA.. They were apparently depicted as the god Enlil, who was the leader of the Babylonian pantheon and special patron of farmers..The name Boötes was first used by Homer in his Odyssey as a celestial reference point for navigation, described as "late-setting" or "slow to set", translated as the "Plowman"...Another myth associated with Boötes by Hyginus is that of Icarius, who was schooled as a grape farmer and winemaker by Dionysus. Icarius made wine so strong that those who drank it appeared poisoned, which caused shepherds to avenge their supposedly poisoned friends by killing Icarius. Maera, Icarius's dog, brought his daughter Erigone to her father's body, whereupon both she and the dog committed suicide. Zeus then chose to honor all three by placing them in the sky as constellations: Icarius as Boötes, Erigone as Virgo, and Maera as Canis Major or Canis Minor...Arcturus, or Alpha Boötis, is the brightest star in Boötes and the fourth brightest star in the sky at an apparent magnitude of −0.04; it has an absolute magnitude of −0.2. It is also the brightest star north of the celestial equator, barely brighter than Vega and Capella.. Its name comes from the Greek for "bear-keeper". An orange giant with color visible from Earth at a distance of 37 light-years, its diameter is 27 solar diameters, equivalent to approximately 32 million kilometers, though its mass is approximately one solar mass.. Its luminosity is 115 L☉ and its spectral class is K2.. Bayer located Arcturus above the herdsman's left knee in his Uranometria..In his Uranometria, Johann Bayer used the Greek letters Alpha through to Omega and then A to k to label what he saw as the most prominent 35 stars in the constellation, with subsequent astronomers splitting Kappa, Mu, Nu and Pi as two stars each. Nu is also the same star as Psi Herculis...

There are several single-planet systems in Boötes.. HD 132406 is a sun-like star of spectral type G0V with an apparent magnitude of 8.45, 231.5 light-years from Earth.. It has a mass of 1.09 solar masses and a radius of 1 solar radius.. The star is orbited by a gas giant, HD 132406 b, discovered in 2007.. HD 132406 orbits 1.98 AU from its host star with a period of 974 days and has a mass of 5.61 Jupiter masses.. The planet was discovered by the radial velocity method..WASP-23 is a star with one orbiting planet, WASP-23 b...Zeta Boötis is a triple star that consists of a physical binary pair with an optical companion.. Lying 205 light-years away from Earth, The physical pair has a period of 123.3 years and consists of a magnitude 4.5 and a magnitude 4.6 star. The two components are separated by 1.0 arcseconds at an angle of 303 degrees. The optical companion is of magnitude 10.9, separated by 99.3 arcseconds at an angle of 259 degrees. 44 Boötis is an eclipsing variable star. The primary is of variable magnitude and the secondary is of magnitude 6.2; they have an orbital period of 225 years.. The components are separated by 1.0 arcseconds at an angle of 40 degrees..44 Boötis (i Boötis) is a double variable star 42 light-years away. It has an overall magnitude of 4.8 and appears yellow to the naked eye. The primary is of magnitude 5.3 and the secondary is of magnitude 6.1; their orbital period is 220 years. The secondary is itself an eclipsing variable star with a range of 0.6 magnitudes; its orbital period is 6.4 hours.. It is a W Ursae Majoris variable that ranges in magnitude from a minimum of 7.1 to a maximum of 6.5 every 0.27 days..All of the Bootid-Coronae Borealid showers are Jupiter family comet showers; the streams in the complex have highly inclined orbits..The placement of Arcturus has also been mutable through the centuries.. Traditionally, Arcturus lay between his thighs, as Ptolemy depicted him. However, Germanicus Caesar deviated from this
tradition by placing Arcturus "where his garment is fastened by a knot"...

Soon afterwards, another vehicle went past on main beam and illuminated a road sign up ahead.. Chris was gutted by what it said. He was 30 milesfurther from the border than he'd estimated. That equated to another two nights of travel, which depressed him severely..When it came to first light, Chris couldn't find a decent LUP and started flapping.. After a lot of running around, he eventually got into a big culvert under the main road. That seemed to be fine, until he heard the ominously familiar sound of goat bells..A herd of goats was coming up the culvert--heading, he supposed, for the fields on the other side. Chris legged it from his hiding place and managed to scramble about 6 feet up the embankment before an old goat herder emerged, followed by a donkey and the world's supply of goats--and a pair of dogs.. They were bound to scent him. He had a split second in which to decide whether to shoot the old man to be on the safe side, or just do a runner..The dogs made the decision for him, running straight past without looking up..The rest of the procession followed without a flicker. Chris couldn't believe it. He had been within spitting distance of them all. He could only think that the dogs had been put off by the scent of the goats-or that of the old boy's dirty dish dash..They would almost certainly be going back that way before last light,however, so Chris knew that he'd have to move. He started crawling along a wadi, having to get down every time a vehicle went along--which was often..The ground had changed by now, from lush, irrigated vegetation to wadi systems and small mounds covered with thorn bushes. It was hard going.. After about 5 miles he found a large depression in the ground and settled down for the rest of the day..Abell 1991 is a galaxy cluster in the Abell catalogue..The original catalog of 2,712 rich clusters of galaxies was published in 1958 by George O. Abell (1927–83), who was then studying at the California Institute of Technology..Interestingly, the extremely large and extremely rich Virgo Cluster was excluded from the Abell catalog because it covered too large an area of the sky to appear on a single photographic plate..Colloquially, its pattern of stars has been likened to a kite or ice cream cone.. However, depictions of Boötes have varied historically.. Aratus described him circling the north pole, herding the 2 bears.. Later ancient Greek depictions, described by Ptolemy, have him holding the reins of his hunting dogs (Canes Venatici) in his left hand, with a spear, club, or staff in his right hand.. After Hevelius introduced Mons Maenalus in 1681, Boötes was often depicted standing on the Peloponnese mountain.. By 1801, when Johann Bode published his Uranographia, Boötes had acquired a sickle, which was also held in his left hand... month, when the moon is full, they hunt as a team..They come ashore at night and have to traverse the mountains to reach their targets..At a pre-designated location..Even moving by night they soon run into trouble..I'm still not convinced these things didn't just escape from the local nut-house...

Last edited by lightgiver; 27-07-2014 at 12:05 AM.
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